Hydrous oxide containing resinous compositions



United States Patent HYDROUS OXIDE CONTAINING RESINOUS COMPOSITIONS Chester A. Amick, Bound Brook, N. 1., assignor to American Cyanamid Company, New York, N. Y., a corporation of Maine No Drawing. Application March 7, 1950, Serial No. 148,279

6 Claims. (Cl. 117-141) The present invention relates to new resinous compositions of matter and more particularly, to the use of the new resinous compositions of matter in the treatment of wool and wool-containing fabrics to reduce their felting, fulling and shrinking tendencies.

Wool and wool-containing fabrics such as loose wool itself, yarns, threads, and woven, felted and knitted cloth have a very undesirable tendency to felt and shrink when subjected to ordinary washing operations. The tendency of these wool materials to felt and shrink is due generally to a curling and intertwining of the wool fibers as the fabrics are wetted and subjected to the mechanical movements of the washing process. As a result the fabric becomes more closely compacted, thicker, and has a considerably reduced area.

A number of different methods have been proposed for the treatment of wool and woolen fabrics to prevent felting and shrinking but all of these have not been completely satisfactory. Some treatments damage the fiber and reduce its wearing qualities, others impart an undesirable hand to the fabric, and some treatments are not permanently eifective and may even cause an ultimate increase in shrinkage. Still other shrink-proofing methods are diflicult to apply with uniformity and create hazards to the workmen involved in their applications.

It has been found that wool and wool-containing fabrics such as woven wool, yarns, worsteds, flannels, blankets, shitting, felts, knit goods and the like, whether of all wool or of part wool and part silk, rayon, cotton or the like, may be rendered substantially resistant to felting, fulling and shrinking by the application thereto of alkylated methylol melamines as described in the Johnstone and Van Loo Reissue Patent No. 22,566. The present invention is partly concerned with an improvement in the process of the Johnstone and Van Loo patent.

It is an object of the present invention to produce new resinous compositions.

Another object of the present invention is to provide an improved process for the treatment of Wool and wool-containing fabrics to reduce their felting, fulling and shrinking tendencies.

It is another object of the present invention to produce a wool-containing fabric resistant to felting and shrinking.

The above and other objects are attained by impregnating a wool-containing fabric with a resinous composition comprising an aqueous solution of an alkylated methylol melamine which contains dispersed therein a water-insoluble metallic hydrous oxide.

The invention will be described in greater detail in conjunction with the following specific examples in which proportions are given in parts by weight unless otherwise indicated. These examples are not intended to limit the scope of the invention; they are merely illustrative.

Example 1 45 parts of methylated trimethylol melamine resin prepared as described below are dissolved in 200 parts of water. 1.3 parts of a catalyst consisting of about 88% diammonium-hydrogen-phosphate and about 12% hexamethylenetetramine are dissolved in 100 parts of water and 1.75 parts of cobalt sulfate containing 7 mols of water of crystallization are added to the catalyst solution whereby a precipitate of hydrous oxide forms. This aqueous dispersion is then added to the resin solution with stirring.

Six S-gram woolen skeins which have been naphtha scoured are soaked for 20 minutes in the resinous composition prepared as described above and then squeezed to about a 97.2% pick-up. The skeins are air dried at C. and then cured for 9 minutes at 140 C.

A control treating bath is prepared by following the above procedure for preparation of the resinous composition but omitting the cobalt sulfate. Naphtha scoured woolen skeins are padded with the control treating bath to about pick-up and then air dried and heat treated as above.

Shrinkage control measurements are made on untreated naphtha scoured woolen skeins, those which were treated with the control bath and those which were treated with the resinous composition containing the cobalt hydrous oxide. The results of the shrinkage control measurements, details of which follow the specific examples, are as follows:

1 Average of three individual measnrem ents.

It is apparent from the above that, as already known, the application of methylated methylol melamine resin to wool provides shrinkage control when compared with untreated wool. Furthermore, it is apparent that the addition of 0.1% cobalt as cobalt hydrous oxide to the resin bath improves the shrinkage control imparted to wool by the treatment thereof with methylated methylol melamine.

Example 2 Two- 12" x 12" scoured Wool flannel pieces weighing approximately 35 g. are treated with the resinous composition of Example 1 which contains cobalt hydrous oxide by the procedure described in Example 1. A control wool flannel piece is provided by treatment with the control treating bath of Example 1. These treated pieces of flannel and a scoured but non-resin treated piece are given five washes by the standard procedure outlined on pages 223-226 of the 1943 Year Book of the American Association of Textile Chemists and Colorists, after which the respective cumulative shrinkages are measured. Results observed are as follows:

Example 3 Percent Tiental shrinkage M t 1 9 2 Percent Cobalt B em e sunm-rmo cent 081112 m 40 min. min. min.

Untr 11. 9 25. 4 4a. 2 Control 6. 5 11. 1 18. 8 31. 5 R a s inego be] t 68 2 Skein No.1- 6.6 0.5 0.1 3.3 4.1 4.5 Skein No.2. 6.5 0.6 0.1 3.1 3.3 3.6 SkeinNo.3. 6.5 0.5 0.1 3.1 3.1 4.0

1 Average of three individual measurements.

It will be observed that the shrinkage control using only 6.5% of the methylated trimethylol melamine resin solution containing a cobalt hydrous oxide, or half the quantity of resin used in Examples 1 and 2, is appreciably improved over that imparted by the use of resin alone with no metallic precipitate.

Example 4 45 parts of methylated trimethylol melamine resin are dissolved in 150 parts of water to which are added 50 parts of a 2.6% solution of the catalyst described in Example and 4.5 parts of anhydrous aluminum sulfate. The resin is first dissolved in water. The catalyst is likewise dissolved in a separate container and the aluminum sulfate solution is prepared in a third container. The catalyst solution is added to, and thoroughly mixed with, the resin solution and subsequently the aluminum sulfate solution is added whereupon a precipitate of hydrous oxide orms.

Five-gram untreated wool skeins are treated as described in Example 1 with the following shrinkage control 1 Average of three individual tests.

Example 5 Example 4 is repeated using half as much aluminum sulfate, i. e., 0.1% aluminum. A shrinkage of only 9.3% after 40 minutes is observed for the wool treated with the resinous composition containing aluminum hydrous oxide while wool treated only with the resin exhibited a shrinkage of about 21%.

Example 6 Example 4 is again repeated using an amount of aluminum sulfate to give a solution containing 0.05% aluminum. Cumulative shrinkage for wool after 40 minutes is 13.1% It again is to be compared with 21% shrinkage for wool treated with resin alone.

Example 7 45 parts of methylated trimethylol melamine resin are dissolved in 100 parts of water. 1.3 parts of the catalyst of Example 1 are dissolved in 50 parts of water. A zirconium sulfate solution is prepared by dissolving 100 parts of the following salt: Zr(SO4)2-ZrOSO4-2H2O in 750 parts of normal sulfuric acid. The catalyst is added to the resin solution with stirring, and 10 parts of the zirmnium sulfate solution which contains 2.9% zirconium are added to the resin-catalyst mixture whereupon a pre cipitate of hydrous oxide forms.

Five-gram untreated woolen skeins are soaked for 20 minutes in the bath prepared as described above, squeezed to about a 100% extraction, air dried. at 85 C. and then cured for 10 minutes at 150 C. Shrinkage tests made as in Example 1 give the following results:

Percent Total Shrinkage Material 122 lgf gk m cent 10 min. 20 min. 40 min.

Untreated 11. 9 25. 4 43. 2 ControL. 13 4.0 11.8 20.9 Resin-zirconium treated... 13 0. 083 0. 01 0. 9 1 3. 0

1 Average of three separate tests.

Example 8 The procedure of Example 7 is repeated except that 24.5 parts of the resin solution are used and 20.5 parts additional water are added. The pH of the solution is brought to about 7 with ammonium hydroxide after which wool flannel pieces are impregnated and squeezed to give a wet pick-up of 85%. After a preliminary drying at 80 C., the pieces are cured at 165 C. for five minutes. Cumulative shrinkage measurements made as in Example 2 give 2% shrinkage in the warp and 4% shrinkage in the filling for the treated wool flannel pieces as compared with 44% in the warp and 32% in the filling for untreated control samples.

In the above examples, the percent inorganic salt and percent metal content figures are calculated based on the total weight of the treating solution including resin, catalyst, metallic hydrous oxide-forming material. water, etc.

in some of the preceding examples the shrinkage tests were made on different skeins of yarn which were treated at the same time. This accounts for minor differences in observed shrinkage values as, for example in Example 1, the differences between the shrinkage values for Skein No. 1 and for Skeins Nos. 2 and 3 since the wool may be physically non-uniform. it may be non-uniformly wet by the resin solution and hence contain, in the cured state, non-uniform amounts of resin, or, for a variety of other reasons.

Preparation of methylated trimethylol melamine One mol of melamine is mixed with 3.3 mols of aqueous 37 formaldehyde previously adjusted to a pH of approxi mately 8.0, the temperature being raised to 70 C. and maintained at this point until a clear solution is obtained. The solution is then immediately cooled and allowed to set, and the mass is broken into small pieces and dried by circulating warm air at a temperature not exceeding 55 C. The resulting dried powder is alkylated by admixture with twice its weight of 95% methanol containing 0.5% of oxalic acid crystals, based on the weight of the methylol melamine. The mixture is heated to 70 C. and held at this temperature for approximately 15 minutes, or until a clear solution is obtained, whereupon it is immediately neutralized by the addition of sufiicient sodium hvdroxide solution to raise the pH to approximately 9.0. The neutralized reaction mass is then evaporated to 80% solids under reduced pressure so that the temperature does not rise above 50 C.

Method for making shrinkage tests is practically 90 cm. long. The two ends of the loop are folded over and half-twisted several times to give a small multi-strand loop of about 10 cm. in diameter. This is then loosely tied with a piece of cotton sewing-thread to prevent undue tangling. Three such loops are measured for each test. The three loops are then placed in a 4 oz. glass bottle to which 75 ml. of an 0.1% Lux soap solution "is added. These three skeins are allowed to soak for 20 min. in order to become thoroughly wet, after which the loops are removed from the bottle. pressed gently between the fingers to remove excess liquid. and measured accurately to obtain their wet-length. They are then replaced in the soap solution in the bottle, the cap of the bottle is secured, and the bottle is placed on a shaking machine which has a speed of 312 double shakes per minute. Thus,

the bottle changes direction 624 times each minute. Shaking is then continued for minutes, after which the bottles are opened, the skeins removed, pressed gently, and again measured. The difference between the average of the length of these threepieces and the initial length shows the amount of shrinkage in a 10 minute treatment. The three skeins are then replaced in the original container and given a second 10 minute shaking, after which the bottles are removed, opened, the skeins removed, the excess liquid squeezed out, and the lengths measured as before. This measurement permits computation of the shrinkage for 20 minutes. The procedure is again repeated, that is, the skeins are replaced in the bottles and shaken for 20 minutes additional, and the results at the end of this 20 minute period give the cumulative shrinkage for a period of 40 minutes.

The present invention contemplates the use, in conjunction with an aqueous solution of alkylated methylol melamine resin, of from about 0.025% to about 5%, and preferably from about 0.1% to about 2%, by weight of water-insoluble hydrous oxide-forming metal, calculated as the metal, based on the total weight of the wool treating solution. Thus, when the woolen material picks up 100% of its Weight of the treating solution, it will thereby carry from about 0.025% to about 5% of the hydrous nxideforming metal, calculated as the metal.

The water-insoluble metallic hydrous oxide may be formed in the resinous treating bath by addition thereto of a salt such as the sulfate, nitrate, acetate, chloride, etc., of the metal as set forth in the examples, or it may be added to the treating bath as such and dispersed therein. The present invention is not limited, however, to the presence of the water-insoluble metallic hydrous oxide in the treating bath and if desired, the insoluble oxide may be formed in the fabric itself, for example, by pretreatment of the woolen material with the hydrous oxideforming material followed by treatment with the resin solution or by treatment of the woolen material with the resin solution followed by the hydrous oxide-forming material before the resin is cured.

Any colloidal water-insoluble metallic hydrous oxide may be used in my new resinous compositions. As stated above the hydrous oxide may be dispersed as such in the resin solution or it may be formed therein from a corresponding salt, oxide or hydroxide. Preferred metallic hydrous oxides are those of zinc, titanium, aluminum and zirconium because they are white. However, if a colorless or white product is not required the hydrous oxides of other metals forming them as, for example, cobalt and other metals set forth in the book by Weiser entitled The Hydrous Oxides may be used just as well.

The impregnating solution of resin and water-soluble hydrous oxide may be neutralized to a pH of about 7 by addition of a suitable alkali such as sodium hydroxide, potassium carbonate, ammonium hydroxide, etc. This neutralization step may be desirable, particularly where metal salts having a particularly low pH are used.

Other alkylated methylol melamines than the methylated trimethylol melamine of the specific examples may be used in my compositions. Examples of such useful alkylated methylol melamines include those set forth in the Johnstone and Van Loo Reissue Patent No. 22,566, particularly on page 2, column 1, at lines 49-64.

Shrinkage control of woolen fabrics is most effective and economical within the range of about 5%-15% by weight of resin based on the dried weight of fabric although wool shrinkage is appreciably decreased by as little as 2 /2% by weight of the resin. The pick-up of my compositions by the wool fabric and the resin content thereof should be governed, therefore, so that from 2 /2 %l5% of resin is held in the fabric.

The fabric to be treated is first thoroughly cleaned to remove fats and oils, etc. The dry fabric is then immersed in the resinous composition and passed through suitable rolls as in a padder or mangle to secure uniform impregnation and to remove excess resin. The fabric, however, may be impregnated by other methods such as, for example, by spraying or with suitable boxes located on the mangle or by first impregnating the fabric and then removing the excess liquid by whizzing. As my invention is not limited to any particular method of impregnating the wool fabric, other methods will occur to those skilled in the art.

After the wool has been impregnated with my new resinous compositions it is dried and the resin is cured in situ by the application of elevated temperature. During this resin curing operation it is entirely possible that the metallic hydrous oxide present in the composition may be converted to the corresponding oxide or hydrate thereof so that the finished wool-fabric may contain, besides cured resin, either hydrous oxide or oxide or both.

In order to speed up the curing of the resin and decrease the heating time required for curing, a suitable catalyst may be added to the resinous dispersion. Such catalysts are known to chemists in the resin art and include, for example, diammonium-hydrogen-phosphate, triethanolamine phthalate, and the like. The catalyst in my new resinous compositions may serve the additional function of bringing about formation of the hydrous metallic oxide if the corresponding salt or oxide has been introduced.

Buffering agents such as calcium carbonate, magnesium oxide, urea, the hexamethylene tetramine of the examples and other polyalkylene polyamines boiling above about 200 C., etc., may be incorporated into the treating compositions as desired or as conditions may require. Similarly, my resinous compositions may contain minor quantities of other water-soluble resins such as the alkylated urea-formaldehyde resins, pigments, dyes, .fillers as starch, clay, etc.

The curing temperatures may vary considerably from as low as room temperature (about 20-25 C.) to about 300 C. with a corresponding reduction in time of cure with increase of temperature. I prefer curing at temperatures of from about -150 C.

My process may be employed with colored goods as well as whites without appreciably affecting the colors or shades and without damage to the material. Moreover, my new shrink-proofing process has no deleterious eflect on the fastness to light of dyed wool fabrics.

I claim:

1. A process of reducing the felting and shrinking tendencies of wool-containing fabrics which comprises impregnating a wool-containing fabric with an aqueous dispersion of a water-soluble substantially unpolymerized alkylated methylol melamine condensation product and a water-insoluble metallic colloidal hydrous oxide in suflicient amount to deposit from 2.5 to 15 per cent of the condensation product and from 0.025 to 5 per cent of the hydrous oxide, calculated as the metal, based on the dry weight of the fabric, and thereafter subjecting the impregnated fabric to a temperature sufliciently elevated to cure the condensation product to a substantially waterinsoluble condition.

2. A process according to claim 1 in which the con densation product is methylated methylol melamine.

3. A process according to claim 2 in which the hydrous oxide comprises hydrous zinc oxide.

4. A process according to claim 2 in which the hydrous oxide comprises hydrous titanium oxide.

5. A process according to claim 2 in which the hydrous oxide comprises hydrous aluminum oxide.

6. A process according to claim 2 in which the hydrous oxide comprises hydrous zirconium oxide.

References Cited in the file of this patent UNITED STATES PATENTS Re. 22,566 Johnstone et a1 Nov. 21, 1944 2,200,164 Durant May 7, 1940 2,476,939 Wise July 19, 1949 2,566,964 Scholz et a1 Sept. 4, 1951 FOREIGN PATENTS 313,771 Great Britain June 20, 1929 OTHER REFERENCES Mellor, A Comprehensive Treatise on Inorganic and Theoretical Chemistry, vol. 5, Longman Green, New York (1924), page 269. 

1. A PROCESS OF REDUCING THE FELTING AND SHRINKING TENDENCIES OF WOOL-CONTAINING FABRIC WHICH COMPRISES IMPREGNATING A WOOL-CONTAINING FABRIC WITH AN AQUEOUS DISPERSION OF A WATER-SOLUBLE SUBSTANTIALLY UNPOLYMERIZED ALKYLATED METHYLOL MELAMINE CONDENSATION PRODUCT AND A WATER-INSOLUBLE METALLIC COLLOIDAL HYDROUS OXIDE IN SUFFICIENT AMOUNT TO DEPOSIT FROM 2.5 TO 15 PER CENT OF THE CONDENSATION PRODUCT AND FROM 0.025 TO 5 PER CENT OF THE HYDROUS OXIDE, CALCULATED AS THE METAL, BASED ON THE DRY WEIGHT OF THE FABRIC, AND THEREAFTER SUBJECTING THE IMPREGNATED FABRIC TO A TEMPERATURE SUFFICIENTLY ELEVATED TO CURE THE CONDENSATION PRODUCT TO A SUBSTANTIALLY WATERINSOLUBLE CONDITION. 